This invention generally relates to the treatment of hides and leathers and, more particularly, to drum apparatus for effecting such treatment in a softer and more efficient manner than is possible utilizing conventional apparatus.
Hides and leathers are conventionally treated in rotating drum apparatus containing a bath including tanning, dyeing and other materials. Conventional drum apparatus include stakes or paddles which move the hides through the bath and then raise them to a pre-determined height from which they are dropped into the bath thereby intensifying the diffusion of the bath into the hides.
Since the above-described operation necessarily results in hides impacting both against the bath and against each other, conventional drum apparatus are generally not used for hides having hair or fur since the impacts which occur felt or mat or otherwise damage the fur or hair irreversibly.
In order to diminish the effect of the impacts, the rotational speed of the drum apparatus has been reduced. However, this has the drawback of reducing the agitation to which the hides or leather are subjected thereby slowing the rate of diffusion of the tanning, dyeing and other materials of the bath through the hides and resulting in irregularities in the operation and treatment.
Attempts have been made to overcome the drawbacks discussed above by providing the drums with paddles which are inclined relative to the generatrix of the cylinder at alternately opposite angles so that the hides tend to shift from one side to the other. However, the results obtained using this provision have not been entirely satisfactory.